Professor Tim Spector, an expert on telomeres and ageing based at King's College London, said: "The study and resulting theory is plausible as researchers have found previous telomere links with chronic stress.

"However, many different adverse environments are known to reduce telomeres - such as cigarette smoking, obesity, lack of exercise and social class as well as genes.

"In such a small sample such as this - any of these could actually be responsible rather than the abuse - so it needs replication on a much bigger scale."